#include<iostream>
#include<vector>
#include<algorithm>
using namespace std;

int main()
{
	vector<int> ret(10);
	ret = { 1,2,3,4,5,6,7,8 };
	sort(ret.begin(), ret.end());

	if (ret.size() % 2 == 0)
	{
		cout << (double)(ret[ret.size() / 2] + ret[ret.size() / 2] - 1) / 2 << endl;
	}
	else
	{
		cout<< (double)ret[ret.size() / 2]<<endl;
	}
	return 0;
}